1. Field of the Invention
The present invention is concerned with protection against high intensity focused ultrasound (HIFU) reflection and far field heating.
2. Description of the Prior Art
Magnetic resonance guided high intensity focused ultrasound (MRg HIFU) is a hybrid technology that offers efficient and safe thermal ablation of targeted tumors or other pathological tissues, while preserving the healthy surrounding structures. Theoretically, MRgHIFU has no limitation as to the size of the lesion that can be treated. The primary challenge is to avoid near and far field heating that occur due to the continued passage of HIFU through tissue after the region of interest has been irradiated. Particularly at the patient body location at which the radiation exits the patient's body, reflection and heating can occur due to the tissue/air interface at that location. This location is typically approximately opposite the entry point of HIFU into the patient's body, with the region of interest being between the entry location and the exit location.